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Peter Lind

Publications and source records attributed to Peter Lind.

34 records · Page 2Linked to original sources

Fluorine-18-fluorodeoxyglucose positron emission tomography in the preoperative assessment of thyroid nodules in an endemic goiter area.

BACKGROUND: The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the preoperative assessment of suspicious thyroid nodules. METHODS: A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq (18)F-FDG. Standard uptake values (SUVs) were calculated. RESULTS: A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. (18)F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 +/- 2.2, 3.7 +/- 1.9, 1.6 +/- 0.3, 1.2 +/- 0.2, and 0.9 +/- 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used. CONCLUSIONS: Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. (18)F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded.

Adenoma↗

F-18 fluorodeoxyglucose positron-emission tomography in the diagnosis of tumor recurrence and metastases in the follow-up of patients with breast carcinoma: a comparison to conventional imaging.

AIM: To evaluate the role of F-18-fluorodeoxyglucose positron-emission tomography (F-18 FDG PET) in the follow-up of breast carcinoma in case of clinical suspicion of local recurrence or distant metastases and/or tumor marker increase in correlation to conventional imaging. MATERIAL AND METHODS: Retrospective analysis of the results of F-18 FDG PET (ECAT ART(R), Siemens CTI MS) of 62 patients (age 58.5 +/- 12.8) with surgically resected breast carcinoma (time interval after surgery, 86 +/- 82 months, mean follow-up 24 +/- 12.6 months). Patient- and lesion-based comparison with conventional imaging (CI) including mammography (MG), ultrasonography (US), computerized tomography (CT), magnetic resonance imaging (MRI), radiography (XR) and bone scintigraphy (BS). Furthermore, we evaluated the influence on tumor stage and therapeutic strategy. A visual qualitative evaluation of lesions was performed. RESULTS: On a patient base, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for detecting local recurrence or distant metastases were calculated to be 97%, 82%, 87%, 96% and 90% compared with 84%, 60%, 73%, 75% and 74% with CI. On a lesion base, significantly more lymph node (84 vs. 23, P < 0.05) and fewer bone metastases (61 vs. 97, P < 0.05) could be detected by using F-18 FDG PET compared with CI. Sclerotic bone lesions were predominantly detected by BS. On the other hand, there were several patients with more FDG positive bone lesions and also mixed FDG positive/Tc-99m methylenediphosphonate (MDP) negative and FDG negative/Tc-99m MDP positive metastases. In case of normal tumor markers, sensitivity, specificity, PPV, NPV and accuracy for detecting local recurrence or distant metastases were calculated to be 100%, 85.0%, 78.6%, 100% and 90.3% for FDG PET and 80%, 50%, 50%, 80% and 61.5% for CI. An upstaging could be observed in 9.7% (6/62) and downstaging in 12.9% (8/62), leading to a change in therapeutic regimen in 13 patients (21%). CONCLUSIONS: F-18 FDG PET demonstrates apparent advantages in the diagnosis of metastases in patients with breast carcinoma, compared with conventional imaging on a patient base. On a lesion base, significantly more lymph node and less bone metastases can be detected by using F-18 FDG PET compared with conventional imaging, including bone scintigraphy. In patients with clinical suspicion but negative tumor marker profile, too, F-18 FDG PET seems to be a reliable imaging tool for detection of tumor recurrence or metastases. Considering the high predictive value of F-18 FDG PET, tumor stage and therapeutic strategy will be reconsidered in several patients.

Biomarkers, Tumor↗

Inflammation-sensitive plasma proteins and incidence of myocardial infarction in men with low cardiovascular risk.

OBJECTIVE: Myocardial infarction (MI) is sometimes experienced by individuals without any traditional risk factor. This prospective study explored whether incidence of MI in nonsmoking, nondiabetic men with normal blood pressure and serum lipids is related to inflammation-sensitive plasma proteins (ISPs). METHODS AND RESULTS: Five ISPs (alpha1-antitrypsin, haptoglobin, ceruloplasmin, fibrinogen, orosomucoid) were analyzed in 6075 men, 47+/-3.6 years old. A low-risk group (no traditional risk factor, n=1108) and a high-risk group (> or =2 major risk factors, n=1011) were defined. Incidence of MI (n=227) was monitored over 18.1+/-4.3 years of follow-up. In the low-risk group, the age-adjusted relative risks (RRs) were 1.00 (reference), 1.9 (95% CI, 0.8 to 4.2), 1.8 (95% CI, 0.6 to 5.4), and 2.9 (95% CI, 1.05 to 8.1), respectively, for men with 0, 1, 2 and > or =3 ISPs in the top quartile (trend: P=0.03). In this group, the increased risk was observed only after > or =10 years of follow-up. In the high-risk group, the age-adjusted RRs were 1.00, 1.4 (95% CI, 0.9 to 2.2), 1.9 (95% CI, 1.2 to 3.1), and 2.0 (95% CI, 1.3 to 3.1), respectively, for men with 0, 1, 2, and > or =3 ISPs in the top quartile (trend: P=0.0004). CONCLUSIONS: Incidence of MI in nonsmoking, nondiabetic men with normal blood pressure and lipids was related to ISPs. The causes for this relationship remain to be explored.

Acute-Phase Proteins↗

Inflammation-sensitive plasma proteins, diabetes, and mortality and incidence of myocardial infarction and stroke: a population-based study.

This study explores the relationship of inflammation-sensitive plasma proteins (ISPs) with the prevalence of diabetes and the interrelationships between ISPs and diabetes in the prediction of death and incidence of myocardial infarction and stroke. Plasma levels of fibrinogen, alpha1-antitrypsin, haptoglobin, ceruloplasmin, and orosomucoid were assessed in 6,050 men, aged 28-61 years. All-cause and cardiovascular mortality and incidence of myocardial infarction and stroke were monitored over 18.7 +/- 3.7 years. Prevalence of diabetes (n = 321) was significantly associated with ISP levels among overweight and obese men but not among men with BMI <25 kg/m(2). The association was similar for insulin resistance according to homeostasis model assessment. High ISP levels (two or more ISPs in the top quartile) increased the cardiovascular risk among diabetic men. The risk factor-adjusted relative risks for cardiovascular mortality, myocardial infarction, and stroke were 2.8 (CI 1.8-4.5), 2.2 (1.5-3.2), and 2.5 (1.4-4.6), respectively, for diabetic men with high ISP levels (reference: nondiabetic men with low ISP levels). The corresponding risks for diabetic men with low ISP levels were 1.8 (1.1-3.0), 1.3 (0.8-2.1), and 1.2 (0.6-2.5), respectively. In conclusion, in this population-based cohort, diabetes was associated with increased ISP levels among overweight and obese men but not among men with normal weight. High ISP levels increased the cardiovascular risk similarly in diabetic as compared with nondiabetic men.

Blood Pressure↗

Inflammation-sensitive plasma proteins are associated with future weight gain.

Cross-sectional studies have associated obesity and other components of the so-called metabolic syndrome with low-grade inflammation. The temporal and causal relations of this association have not been fully explored. This study explored whether elevated levels of inflammation-sensitive plasma proteins (ISPs) (fibrinogen, orosomucoid, alpha1-antitrypsin, haptoglobin, and ceruloplasmin) are associated with future weight gain. Five ISPs were measured in 2,821 nondiabetic healthy men (38-50 years of age) who were reexamined after a mean follow-up of 6.1 years. Future weight gain was studied in relation to the number of elevated ISPs (i.e., in the top quartile). The proportion with a large weight gain (75th percentile >/= 3.8 kg) was 21.0, 25.9, 26.8, and 28.3%, respectively, among men with none, one, two, and three or more ISPs in the top quartile (P for trend 0.0005). This relation remained significant after adjustments for weight at baseline, follow-up time, height (at baseline and follow-up), physical inactivity (at baseline and follow-up), smoking (at baseline and follow-up), high alcohol consumption, and insulin resistance. The relations were largely similar for all individual ISPs. Elevated ISP levels predict a large weight gain in middle-aged men. This relation could contribute to the relation between inflammation, the metabolic syndrome, and cardiovascular disease.

Adult↗

Blood pressure increase and incidence of hypertension in relation to inflammation-sensitive plasma proteins.

OBJECTIVE: The reasons for the relationship between inflammation-sensitive plasma proteins (ISPs) and incidence of cardiovascular diseases are poorly understood. This study explored the hypothesis that ISPs are associated with future hypertension and age-related blood pressure increase. METHODS AND RESULTS: Blood pressure and plasma levels of fibrinogen, alpha1-antitrypsin, haptoglobin, ceruloplasmin, and orosomucoid were determined in 2262 healthy men aged 35 to 50 years, initially without treatment for hypertension. The cohort was re-examined after 15.7 (+/-2.2) years. Incidence of hypertension and blood pressure increase was studied in relation to number of elevated proteins (ie, in the top quartile) at baseline. Among men without treatment for hypertension at follow-up, mean (+/-SD) increase in systolic blood pressure was 18.8+/-17, 19.2+/-17, 19.3+/-17, and 22.1+/-18 mm Hg, respectively, for men with 0, 1, 2, and > or =3 elevated proteins (P for trend=0.02, adjusted for confounders). The corresponding values for pulse pressure increase was 15.5+/-14, 15.8+/-14, 17.4+/-14, and 17.8+/-15 mm Hg, respectively (P=0.02). Incidence of hypertension (> or =160/95 mm Hg or treatment) and future blood pressure treatment showed similar associations with ISPs. Increase in diastolic blood pressure showed no association with ISPs. CONCLUSIONS: Plasma levels of ISPs are associated with a future increase in blood pressure. This could contribute to the relationship between ISP levels and cardiovascular disease.

Adult↗

Strategies of radioiodine therapy for Graves' disease.

Several therapeutic options are available for the treatment of Graves' disease (GD), including long-term antithyroid drug medication (ATD), near-total resection (NTR) and radioiodine therapy (RIT). These treatments are used with different frequencies depending on geographical location, size of the goitre, age of the patient and experience of the physician. It should be noted that RIT is still being applied more frequently in the United States than in Europe. Despite the fact that RIT was introduced as long ago as 1941, several questions are still the subject of debate: Should a fixed dose or a calculated dose be used. If the dose is calculated, how many Grays (Gy) should be delivered to the thyroid? What is the goal of RIT in GD? Which factors, including ATD, influence the outcome of RIT? Is RIT appropriate in GD with Graves' ophthalmopathy (GO)? Although not all these questions have been answered yet, conclusions can be derived regarding a general strategy for use of RIT in GD. As with surgery, the goal of RIT in GD is euthyroidism with or without L-thyroxine medication. There is a clear advantage of dose calculation over use of a fixed dose because the only factor influencing the outcome is the dose delivered to a certain thyroid volume. To minimise recurrent hyperthyroidism, an ablative approach using a delivered dose of 250 Gy is widely accepted. Beside pretherapeutic T(3) levels, thyroid volume and 24-h thyroid uptake, ATD may influence the outcome of RIT. Today it is accepted by most thyroidologists that, if ATD medication is necessary in overt hyperthyroidism, it should be withdrawn at least 2 days before RIT. In patients with GD and GO, RIT may worsen GO. If RIT is performed in GO it should be done under a 3-month steroid medication regimen. In conclusion, RIT can be considered an appropriate and cost-effective therapy in GD, although the decision regarding treatment should be taken on an individual basis, paying due respect to the course and severity of disease, the presence of GO and, last but not least, the wishes of the patient.

Adrenal Cortex Hormones↗

Immunochemical analyses of serum antibodies from pig herds in a Salmonella non-endemic region.

In a large comparative survey of Danish and Swedish slaughter pig herds performed prior to this work, it was unexpectedly found that some Swedish herds harbored seropositive pigs. Serum samples from the Swedish herds had moderate responses in the Salmonella mix-ELISA (detecting serogroup B and C1 infections) compared to the Danish herds classifying some of them as seropositive using a cut-off value at 40 OD%. In Sweden, extensive Salmonella control is carried out by bacteriological screening of feces and lymph nodes, and the overall prevalence has been proven to be below 0.1%. The serological positive results were therefore unexpected; hence the reactivities of the Swedish sera were studied by a number of immunochemical analyses (Western blot, indirect ELISA, inhibition ELISA, avidity ELISA) and compared to sera from Danish pig herds with verified Salmonella infections ("the reference sera"). In Western blot, the Swedish sera had high binding reactivities against Salmonella Typhimurium LPS of different molecular weights, and gave binding patterns similar to that of the reference sera. Pre-incubation with free S. Typhimurium LPS or PS (the polysaccharide part of LPS) was able to inhibit the reactivity of the Swedish sera in the mix-ELISA. Reactivities against other related bacterial LPS such as Citrobacter freundii LPS and Yersinia enterocolitica O:3 LPS were observed in the Swedish sera, but these LPS antigens were unable to inhibit the reactivities in the mix-ELISA as efficiently as S. Typhimurium LPS. Furthermore, the Swedish sera did not bind Salmonella LPS of another serogroup (S. Meleagridis LPS, serogroup E1) or rough Salmonella LPS, both lacking the specific O-antigenic parts of S. Typhimurium LPS. The avidity of the Swedish sera was much lower than the avidity of the reference sera, which could indicate the presence of transient low-dose infections or stimulation by inactivated bacteria in feed. The results obtained in this investigation strongly indicate that the Swedish sera contain antibodies directed against the O-antigenic part of LPS from S. Typhimurium or possibly on as yet unknown bacterium.

Animals↗

Serological survey of Toxoplasma gondii infection in pigs slaughtered in Sweden.

The prevalence of Toxoplasma gondii infection in Swedish pigs was investigated by analysis of 807 meat juice samples collected in 1999 from 10 abattoirs in different parts of the country. When analysed using ELISA, 42 (5.2%) of the samples were found to be positive. The seroprevalence was 3.3% in fattening pigs (n = 695) and 17.3% (n = 110) in adult swine. Alternative interpretations of the results, considering estimates of the true prevalence based on the sensitivity and specificity of the test method, are discussed. It is concluded that the risk of contracting T. gondii infection as a result of eating undercooked pork from Swedish pigs, especially adult animals, is not negligible.

Abattoirs↗

Goiter prevalence and urinary iodide excretion in a formerly iodine-deficient region after introduction of statutory lodization of common salt.

The objective of this epidemiologic study was to determine the volume of the thyroid gland as well as urinary iodine excretion in dependence on age and gender in a population from an area of low natural iodine supply now receiving iodine prophylaxis. In 430 persons from three communities in the province of Carinthia, Austria, we determined thyroid volume via sonography as well as urinary iodide excretion. As in numerous other European countries, natural iodine supply is insufficient in Austria. Therefore, to reduce goiter incidence, iodization of common salt with 10 mg potassium iodide (KI) per kilogram of NaCl was made mandatory in Austria in 1963 by federal law. In 1990, the amount of iodine addition was increased to 20 mg KI per kilogram of NaCl. Our results show that mean urinary iodide excretion in the persons investigated was altogether satisfactory (males: 163.7 microg of iodine per gram of creatinine; females: 183.3 microg of iodine per gram of creatinine). Goiter prevalence was 34.3% in women and 21.3% in men. An increase in goiter occurrence with age was noted in both genders. The increase in goiter prevalence was particularly obvious in the age group older than 40, i.e., among those participants who had spent at least a certain span of their lives in an area of iodine deficiency. Thus, the most likely reason for the persistently high goiter prevalence is not current iodine deficit but rather the high number of goiters that had developed previously at the time of iodine deficiency and were unable to undergo regression in spite of today's comparatively good iodine supply situation.

Adolescent↗

A novel Mammalian homologue of a bacterial citrate-metabolizing enzyme.

Mammals metabolize citrate to acetyl-CoA and oxaloacetate via the enzyme, ATP:citrate lyase. Bacteria lack this enzyme, but have the ability to cleave citrate in the form of citryl-CoA in an analogous manner using a structurally distinct enzyme. We have identified a novel mammalian gene that shows significant amino acid sequence homology to the bacterial CitE gene product that is responsible for cleavage of citryl-CoA. We propose that this gene encodes an enzyme that catalyzes cleavage of substrates related to CoA esters of citrate or an analogous intermediary metabolite. The product of this novel gene may represent a component of an unknown metabolic pathway in mammals.

Amino Acid Sequence↗

Support vector machines for the estimation of aqueous solubility.

Support Vector Machines (SVMs) are used to estimate aqueous solubility of organic compounds. A SVM equipped with a Tanimoto similarity kernel estimates solubility with accuracy comparable to results from other reported methods where the same data sets have been studied. Complete cross-validation on a diverse data set resulted in a root-mean-squared error = 0.62 and R(2) = 0.88. The data input to the machine is in the form of molecular fingerprints. No physical parameters are explicitly involved in calculations.

Journal Article↗

A database-centric virtual chemistry system.

We describe an Oracle database application for general use within virtual chemistry. The application functions as a central hub and repository for chemical data with interfaces to external calculators. It deals with the general problems of merging data from disparate sources and with scheduling of computational tasks for parallel or sequential execution in a mixed environment. The central database is used for the storage of input, intermediary, and final data as well as for job control. A calculation job is split into distinct tasks, or units of work, which are put in a queue. Tasks are dequeued and handled by specialized calculators. These calculators are in-house or commercial programs for which adaptor modules for connection to the database must be written. Tasks are handled in a transactional fashion, so that uncompleted or failed tasks are left in the queue. This makes the system stable to many types of disturbances. Sorting, filtering, and merging operations are handled by the database itself. Usage is very general, but some specific examples are (1) as a back end for a chemical property calculator Web page, (2) in an automated quantitative structure-activity relationship system, and (3) in virtual screens.

Journal Article↗

Risk of myocardial infarction in relation to plasma levels of homocysteine and inflammation-sensitive proteins: a long-term nested case-control study.

Several studies have found that the homocysteine plasma level is associated with cardiovascular disease. The authors previously described a relationship between concentrations of fibrinogen and other inflammation-sensitive plasma proteins, namely, alpha1-antitrypsin, ceruloplasmin, haptoglobin, and orosomucoid (alpha1-acid glucoprotein) and the incidence of myocardial infarction (MI). Whether levels of these proteins are related to homocysteine has not been clarified. The aim of this study was to investigate whether a supposed relationship between homocysteine in plasma and the occurrence of MI is modified by these inflammation-sensitive proteins. A nested case-control study was designed, comprising 241 cases of MI, with a mean age of 48 years at baseline, and 241 controls matched for age, month of examination, and duration of follow-up. The mean homocysteine concentration did not differ between cases and controls and there was no association between the baseline homocysteine level and the time lapse before the occurrence of the MI. For the cases, there was no correlation between homocysteine and any of the measured proteins, but for the controls, homocysteine was weakly but significantly negatively correlated to haptoglobin and ceruloplasmin and slightly positively correlated to albumin. For the separated groups of cases and controls there was no association between the number of inflammation-sensitive proteins in the top quartiles and homocysteine concentration. In this population-based, prospective cohort study the occurrence of MI had no relationship to homocysteine baseline plasma level. Furthermore, there was no strong association between homocysteine and the concentrations of any of these inflammation-sensitive proteins.

Blood Proteins↗

Incidence of myocardial infarction and death in relation to walking-induced calf pain and plasma levels of inflammation-sensitive proteins.

Walking-induced calf pain as well as levels of different inflammation-sensitive plasma proteins (ISPs) are related to cardiovascular disease (CVD). This prospective cohort study explored the relationship between ISPs and walking-related calf pain and the interrelationships between ISPs and calf pain in the prediction of death and incidence of coronary events (CE). In 5,725 apparently healthy men, 46 +/-3.0 years old, plasma concentrations of orosomucoid (alpha(1)-acid glycoprotein), alpha(1)-antitrypsin, haptoglobin, fibrinogen, and ceruloplasmin were measured. Walking-induced calf pain was assessed by questionnaire. Mortality and incidence of CE were monitored over a mean follow-up of 18 years in subjects defined by the presence of calf pain and ISP level (0 to 1 or 2 to 5 ISP(s) in the top quartile). The prevalence of calf pain (7.3%) was significantly related to age, lifestyle, and traditional risk factors of CVD and ISP levels. The risk factor-adjusted relative risks for CE, CVD- and all-cause mortality were 1.89 (CI: 1.27 to 2.82), 2.90 (CI: 1.82 to 4.62), and 2.67 (CI: 1.97 to 3.57), respectively, for men with calf pain and high ISP levels (reference: no calf pain and low ISP levels). The corresponding risk for those with calf pain and low ISP levels were 1.34 (CI: 0.91 to 1.97), 1.47 (CI: 0.90 to 2.41), and 1.31 (CI: 0.95 to 1.81), respectively. These results indicate, on the one hand, that walking-induced calf pain is associated with high ISP levels and, on the other, that the risk of CVD in men with calf pain is substantially higher in those with high ISP levels than in those with low levels.

Adult↗